Answer:
We must have less than 10 guests
Explanation:
Location 1
cost = 100h+20p where h = hours and p = person
Location 2
cost = 600 for p < 25
Since there are less than 25 guests and h = 4 both equations are valid
Location 1
cost = 100(4)+20p = 400+20p
Location 2
cost = 600
We want location 2 to be less expensive
600< 400+20p
Subtract 400 from each side
600-400 < 20p
200 <20p
Divide by 20
200/20 < 20p/20
10 <p
We must have less than 10 guests